Edwaed a



(No Model.)

B. A. WILDT.

ELECTRIC BELL.

No. 358,910. Patented Mar 8, 188-7.

N. PETERS, Phnto-Lilhcgraplmr. Wmhlnglon. at:

UNITED STATES PATENT OFFICE.

EDIVARD A. \VILDT, OF LONG ISLAND CITY, NEJV YORK.

ELECTRIC BELL.

SPECIFICATION forming part of Letters Patent No. 358,310, dated March 8,1887. Application filed July 6,1886. Serial No. 207,287. (No model.)

To aZZ whom it may concern.-

Be it known that I, EDWARD A. WILDT, a citizen of the United States,residing at Long Island City, in the county of Queens and State of NewYork, have invented certain new and useful Improvements in ElectricBells,of which the following is a specification.

My invention relates to that class of electric bells that have theoperating parts secured to a plate, projections being provided for thatpurpose and inclosed bya box or cover to protect them from theatmosphere, dust, and insects. I

The objects of my invention are to arrange, distribute, and proportionthe operating parts in such manner that the least possible space isthereby occupied and yet produce a perfect working bell, thus reducingthe amount of material necessary and heretofore used, and to facilitatethe iinanufacture to a degree heretofore not obtained, and also toarrange that part carrying and supporting the operating parts so that itmay be readily and easily removed from its base or wall plate forinspection or repair and again returned without it being necessary toremove the part fastened to the wall, thus avoiding damage to theplaster or defacing the wall in any way, and also to provide certainimproved details in construction hereinafter described.

In the accompanying drawings, which illustrate my invention, Figure 1 isa vertical transverse section on line or a of Fig. 2. Fig. 2 is a planview of the same with the cover in section on line 7 1/ of Fig. 1.

Similar letters of reference refer to similar parts. I

Referring to the drawings, A represents the wall plate or base, to whichis secured the box or cover B, both preferably made of iron, by screw 0passing centrally through it, projections e e c 0 serving to retain itin a certain position, so that it may be removed and returned to exactlythe same position at once. mand m are the twolegs of an eleetro-magnet,with their coils of insulated wire secured to the sides of cover B byscrews a 11, cover B serving as the yoke.

K is its armature, carrying hammer-rod K and ball 0 and supported byspring it, screw g securing it to the side of cover B. Screw 9 alsosupports the binding-post 0 on the outside of cover B,binding-post 0serving as a nut to screw 9 for placing a strain on spring 7i, screwgthus securing both spring h and post 0 one to the inside and the otherto the outside of cover B. The metal washer fis inserted to prevent anylateral vibration of armature K.

Spring h has a narrowed extension, h, carrying a small piece of platinumsoldered to it. One terminalof the coil of insulated wire surroundingelectro-inagnet m is secured under the washer f, making connectiontherewith to the screw 9 and insulated from cover B by the insulationrepresented by letter P.

To prevent the bindingpost o from cutting the insulation when a strainis applied to it sufficient to retain the post in its place, washer f isinserted between it and the insulation. I find that if post 0 is notscrewed up tight and thumb-screw It is, and it is desired to inspect theoperating parts, in attempting to loosen thumb-screw R post 0 willloosen instead, thus causing annoyance and delay. By inserting the metalwasher f beneath the head of screw 9 and the metal washer f between post0 and insulation P, I can screw up post 0, which acts as a nut to screw9 tightly, and with a sufficient strain to prevent its slacking back,when thumbscrew R is loosened without fear of the head of screw g or thebody of post 0 cutting the insulation.

Post 0, screw g, insulation P, washers f and f and one terminal of thecoil of magnet m are supported and insulated from the sides of cover 13.

d, Fig. 2, is a contact-screw carrying a small piece of platinum wire,d, riveted into its point. f and f are metal washers used for the samepurpose described in the case of post 0. d is a thumlrnut working oncontact-screw (I, and is for the purpose of locking screw (1 in anydesired position to prevent its slacking back under the vibration of thebell when ringing. 'v is a bushing threaded centrally for the receptionof contact-screw d, and haw ing aportion of its outside surface reducedand threaded for the reception of nut a, this reduced portion forming ahead or shoulder, so that when screwed up it will not pass entirelythrough washer f.

It will be seen that it is necessary to have bushing 19 screwed uptightly and sufficiently to prevent its turning when it is desired toloosen thumbnutd. To preventtheshoulderofbushing 1; and also 'the nut cfrom cutting the insulation l, the washers f and f" are inserted, thusmaking it possible to screw up v tightly without incurring thatdifficulty.

One terminal of the wire coil of the electromagnet in is secured beneathwasherj and making connection therewith to nut 1;, bushing o, andcontact-screw d, and insulated from cover B. The other two terminals ofthe bobbins are twisted together, as shown at t.

'w is a piece of soft-rubber tubing to prevent any accidental connectionof the terminal of bobbin m in its passage therefrom to washer f A is agong.

B is a hole in the side of cover B large enough to admit of thevibration of hannnerrod K. A projection, G, is cast on the base or wallplate A for the reception of screw 0, and is countersunk so as to enablethe point of screw 0 to find its place when it is desired to attach thecover with its parts thereto.

8 s are rivets of nonmagnetic material projecting through armature K toprevent the armature K from touching the poles of the magnet,which isdone to prevent what is technically known as sticking, due to residualmagnetism. Plate A carries aprojection, A, cast onto it, to support thegong A, and secured by A. a a are holes for attaching the hell to thewall or other place.

The operation of the construction which I have described is as follows:Either the or the wires (it makes no difference how they go) areattached to the binding-posts 0 and 0, respectively, and secured theretoby thumbscrews R and R. The current in its passage passes, say, frompost 0 to screw thence to Washerfand the terminal of bobbin m inconnection therewith, thence to twisted connection t, through bobbin mand its terminal,passing through soft-rubber tube 10, to washer f, tonut 12, to bushing U,(ZOl1t21Cf/'SC16W d, and platinum point (1, andplatinum point h to spring h,thence to washer fand screw cover B, andout through post 0 to return to the battery. The current in its passagemagnetizes the iron cores of m and m, attracting armature K. An mature Kin this movement toward the magnet takes with it ham merrod K and ball0, spring h removing it from contact with screw (1. This causes a breakor opening of the contact-points and a stoppage of the electric current,there being new no electricity traversing the coils. The cores of m andm are no longer magnetized and have no attraction for its armature,which, due to the tension of spring it, returns innnediatcly to itsoriginal position, establishing again the connection at thecontact-points,and consequently again energizing the magnet, and thismotion it keeps on repeating, ringing the hell by ball 0 striking thegong at every attraction of an mature K until the current stops, all ofwhich operation is well known. The cover B, not having projections ofany kind, makes it easy to place in a gig for the purpose of drilling,which also facilitates the handling of the gig.

I am aware of the patents granted to Edwards and Liin gen, April 26,1881, N 0. 240, 582, and to Edgar XV. Hayazergdune 10, 1884, No. 300,253, and Resisue No. 10,533, of October 21, 1884:.

I am aware that other means may be employed by which the box or cover B,when removed from its base or wall plate, can be returned to exactly thesame position again. I do not, therefore, confine myself to the methoddescribed.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. The combination, substantially as hereinbefore set forth, in anelectric bell, of a wall plate or base, A, having a projection tosupport gong A, and projections O and e e e c, with an inclosing box orcover, B, supporting the operating parts, and screw 0, substantially asdescribed.

2. The combination, substantially as here inbefore set forth, in anelectric bell, with a wall plate or base, A, having projections A, O,and e e e e, of an inclosing box or cover, B, bobbins of insulated wireat m and their iron cores, screws n a, armature K, hammerrod K, ball 0,spring h, non-magnetic pieces 8 s, screw 9, post 0, screw R, screw 9,washers 0, screw R, soft-rubber tube 20, bushing 12, nut 1;, thumb nut(1, thumb screw d, platinum points d and screw A", and gong A,substantially as described.

The combination, in an electric bell,with an inclosing box or cover,B,of a post,0, screws It and g, washer-f, spring h,with its narrowedextension h, armature K, non-magnetic pieces 8 s, platinum point It,hammer-rod K, and ball 0, substantially as described.

4-. In an electric bell, an inclosing box or cover, B, supporting theoperating parts and perforated for the reception of screw 0,substantially as described.

5. The combination, in an electric bell, of spring 72, with its narrowedextension, platinum point h",hammer-rod K, ball 0, armature K,nonmagnetic pieces .9 8, post 0,washer f, and screws R and g,substantially as described.

6. An electric bell consisting of a base or wall plate supporting gong Aand an inclosing box or cover supporting the operating parts,counectedtogether and operating essentially as described, and for the purpose setforth.

ED\VARD A. XVILDT.

Vitnesses:

ALFRED F. XVILDT, HENRY XVILLIAMs.

72 f j" ff, insulation P, insulation P, post

